By the time you have read this, Google will have most likely fixed the “bug”. While it certainly isn’t a feature, or an Easter Egg, it is curious:
The Verge highlighted a Quora post about the bug, where doing some searches for “contradictory” or impossible to solve queries brings back porn listings.
For example, queries like the ones below currently do this (and be forewarned, you’re going to get porn results at Google if you click on these links):
Found at Search Engine Land